iswa landfill operational guidelines 2nd edition

8/21/2019 ISWA Landfill Operational Guidelines 2nd Edition

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LANDFILLOPERATIONAL

GUIDELINES 2nd Edition

PREPARED BY

ISWA WORKING GROUP ON LANDFILL


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P R E F A C E

The Landfill Operations Guidelines were first produced in 2002 as a loose leaf document to

assist waste managers with the day to day operations of landfills. At that time it was not

intended to be a technical document but one providing general guidance which would lead

to improved operational practices.

The guidelines have now been updated by the ISWA Working Group for Landfill to reflect

current operational practice and as appropriate some technical guidance. The guidelines

now include a number of photographs which are used to illustrate the activities described.

The Working Group is particularly indebted to Tony Kortegast (Tonkin and Taylor

International, New Zealand) who has edited the document ensuring consistency.

Contributions from the Working Group were from Derek Greedy (Chair Landfill Working

Group, Warwickshire County Council, UK), Prof. Dr. Günay Kocasoy (President of

Turkish National Committee on Solid Waste, !"#$%&'i University, Turkey), Antonis

Mavropoulos (Chair of Scientific and Technical Committee and EPEM, Greece), Jan

Thrane (Vice Chair Landfill Working Group and Odense Waste Management Company

Ltd., Denmark) Reuben Ossai (President of the Waste Management Society of Nigeria and

The Initiates Ltd., Nigeria), Dr. Bharat Nagar (Jamshedpur Utilities & Services Company

Limited, India), William de Bord (Caterpillar Inc., USA), Steve Hamilton (SCS Engineers,USA) and Diana de Bastos and Helena Bergman (ISWA Secretariat, Austria).

Derek Greedy

Working Group Chair

January 2010


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TAB LE OF CONT ENTS

Preface..........................................................................................................................ii

Table of Contents........................................................................................................iii

Chapter 1: Site Roads................................................................................................ 1

1.1.

Introduction..........................................................................................................1

1.2. Road Types...........................................................................................................1

1.3. Approach Roads and Entrances............................................................................1

1.4. Primary Access Roads..........................................................................................2

1.5. Secondary Access Roads......................................................................................3

1.6. Tertiary Access Roads..........................................................................................4

1.7.

Conclusions...........................................................................................................5

Chapter 2: T he Use of Dail y Cover.............................................................................7

2.1. Introduction...........................................................................................................7

2.2.

Objectives of Daily Cover.....................................................................................7

2.3. Discussion..............................................................................................................8

2.3.1.

Windblown Litter.......................................................................................8

2.3.2.

Odour.........................................................................................................8

2.3.3. Scavenging by Birds..................................................................................8

2.3.4.

Scavenging by Humans.............................................................................8

2.3.5. Infestation by Flies and Vermin.................................................................9

2.3.6.

Fires............................................................................................................9

2.3.7. Visual Appearance.....................................................................................9

2.3.8.

Surface Water Control................................................................................9

2.4.

Daily Cover Types.................................................................................................9

2.5.

Application..........................................................................................................122.6. Soil Use Plan.......................................................................................................12

2.7.

Conclusions.........................................................................................................12

Chapter 3: Bir d Control.............................................................................................13

3.1. Introduction.........................................................................................................13

3.2. Background.........................................................................................................13

3.3. Hierarchy of Controls..........................................................................................14

3.4. Operational Practice............................................................................................14

3.5.

Control Methods..................................................................................................14

3.6. Conclusions.........................................................................................................16


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Chapter 4: W hee l C leaning.......................................................................................17

4.1. Introduction.........................................................................................................17

4.2.

Options for Minimizing Nuisance.......................................................................17

4.3. Hierarchy of Controls..........................................................................................17

4.4.

Discussion...........................................................................................................18

4.5. Conclusion...........................................................................................................18

Chapter 5: L itter Control..........................................................................................21

5.1. Introduction.........................................................................................................21

5.2. Hierarchy of Control Measures...........................................................................21

5.3.

Methods of Control.............................................................................................22

5.3.1. Load Control............................................................................................22

5.3.2. Waste Handling.......................................................................................22

5.3.3. Portable Litter Screens.............................................................................22

5.3.4. Litter Fencing..........................................................................................22

5.3.5. Bunds.......................................................................................................23

5.3.6. Perimeter Fencing....................................................................................23

5.3.7.

Select Tipping Areas...............................................................................23

5.3.8. Netted Areas............................................................................................23

5.3.9.

Designated Waste Transfer Areas...........................................................23

5.3.10.

Methods for Handling Lightweight Waste...........................................245.3.11. Restricting Operating Hours.................................................................24

5.4.

Conclusions.........................................................................................................24

Chapter 6: Vector Control.........................................................................................25

6.1. Introduction.........................................................................................................25

6.2. Background.........................................................................................................25

6.3. Hierarchy of Control...........................................................................................25

6.4. Operational Practice............................................................................................25

6.5.

Monitoring...........................................................................................................26

6.6. Eradication...........................................................................................................27

6.7. Conclusions.........................................................................................................27

Chapter 7: Managing the Wor king Face.................................................................29

7.1. Introduction.........................................................................................................29

7.2. Placement of the First Layer of Waste................................................................29

7.2.1. General.....................................................................................................29

7.2.2.

Procedures for the Construction of the First Layer.................................307.3.

Working Face Management Procedures..............................................................30

7.3.1. Summary..................................................................................................30


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7.3.2.

Use the Smallest Area Practicable...........................................................30

7.3.3. Orderly Truck Movement and Unloading...............................................31

7.3.4.

Work Wastes Together............................................................................327.3.5.

Waste Compaction/Placement.................................................................32

7.3.6.

Working Face Slope................................................................................33

7.3.7. Keep the Working Area Well Drained....................................................33

7.3.8.

Apply and Compact Soil Cover Promptly...............................................33

7.3.9. Disposal of Specific/Difficult Wastes.....................................................33

7.4. Checklist..............................................................................................................35

7.5.

Conclusions.........................................................................................................35

Chapter 8: W aste Compaction..................................................................................37

8.1.

Benefits of Waste Compaction............................................................................378.2.

Compaction Methods..........................................................................................38

8.3. Conclusions.........................................................................................................39

Chapter 9: Landfill Fires...........................................................................................41

9.1. Introduction..........................................................................................................41

9.2.

Characterization of a Fire....................................................................................42

9.3. Immediate Actions...............................................................................................43

9.4. Extinguishment Methods.....................................................................................44

9.4.1.

Water Application....................................................................................44

9.4.2. Excavate and Overhaul............................................................................44

9.4.3. Oxygen Suppression................................................................................44

9.5.

Monitoring and Prevention..................................................................................45

9.5.1. Temperature Monitoring..........................................................................45

9.5.2. Gas Composition Monitoring...................................................................46

9.5.3.

Leachate Management..............................................................................47

9.5.4. Fire Prevention and Control Plan..............................................................47

9.6. Checklist................................................................................................................47

Chapter 10: Stormwater and Sediment Control........................................................49

10.1. Introduction.........................................................................................................49

10.2. Functions of Surface Drainage Systems.............................................................49

10.3. Key Design Elements..........................................................................................50

10.3.1. Overview.................................................................................................50

10.3.2.

Stormwater Detention/Sedimentation/Storage Ponds.............................5010.3.3.

Primary Drainage Systems......................................................................51

10.3.4. Secondary Drainage.................................................................................51

10.3.5.

Tertiary (temporary) Drainage Systems..................................................52


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10.3.6.

Active Area Drainage.............................................................................52

10.3.7. Landfill Cap Drainage............................................................................52

10.4.

Conclusions........................................................................................................53

Chapter 11: W aste Control at Landfills

11.1.

Introduction........................................................................................................55

11.1.1.

Definitions..............................................................................................55

11.1.2. Control Processes...................................................................................55

11.1.3.

Control Infrastructure.............................................................................56

11.1.4. Levels of Control....................................................................................56

11.2. Waste Control Chain of Responsibility..............................................................57

11.2.1. Generator................................................................................................57

11.2.2.

Carrier/Haulage Contractor....................................................................57

11.2.3. Landfill Manager...................................................................................58

11.3. Operational Aspects of Waste Control..............................................................58

11.3.1. Security..................................................................................................58

11.3.2. Entry Point.............................................................................................58

11.3.3. Internal Control......................................................................................59

11.3.4. Work Face Control.................................................................................59

11.3.5.

Reporting................................................................................................59

11.4. Conclusions........................................................................................................60

Chapter 12: Leachate Control....................................................................................61

12.1. Introduction........................................................................................................61

12.2. Discussion of Leachate Control Measures.........................................................62

12.2.1. Appropriate Landfill Siting....................................................................62

12.2.2. Screening for and Restricting Liquid Waste Acceptance.......................62

12.2.3. Landfill Operational Techniques............................................................62

12.2.4. Run-On and Run-Off Controls for Precipitation....................................62

12.2.5.

Liner and Leachate Collection Systems.................................................63

12.2.6. Leachate Treatment................................................................................64

12.3. Conclusions........................................................................................................65

Chapter 13: Odour Control........................................................................................67

13.1.

Introduction........................................................................................................67

13.2. Odour Control Measures....................................................................................67

13.3. Discussion of Odour Control Measures.............................................................68

13.3.1. Restriction on the Acceptance of Odorous Wastes................................68

13.3.2. Properly Covering Wastes..................................................................... 68

13.3.3. Limiting Working Face Size..................................................................68

13.3.4.

Properly Vent, or Collect, Extract and Treat Landfill Gas....................6813.3.5.

Control of Leachate...............................................................................69

13.3.6. Odour Masking......................................................................................69

13.3.7.

Landscaping..........................................................................................70


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13.3.8.

Working Face Location and Special Burials........................................70

13.4. Conclusions......................................................................................................71

Chapter 14: Landfi ll Gas Management ...................................................................73

14.1. Introduction......................................................................................................73

14.2. Landfill Gas Generation...................................................................................73

14.2.1. Phases of Landfill Gas Generation.......................................................73

14.2.2. Landfill Gas Generation Volume.........................................................74

14.2.3.

Landfill Gas Generation Rate...............................................................74

14.2.4. Landfill Gas Composition.....................................................................74

14.3. Landfill Migration and Emissions.....................................................................75

14.4.

Landfill Gas and Control...................................................................................77

14.4.1. Passive Venting Systems.......................................................................77

14.4.2. Active Control Systems.........................................................................78

14.5. LFG Monitoring.................................................................................................78

14.5.1. LFG Migration Monitoring....................................................................79

14.6. Landfill Gas Utilization......................................................................................80

14.6.1. Electric Power Generation......................................................................80

14.6.2. Direct-Use...............................................................................................81

14.6.3.

Pipeline Quality Gas................................................................................8114.6.4.

Other Potential Uses of LFG...................................................................82

14.7. Conclusions.........................................................................................................82

Chapter 15: Guideline for Site Safety and Security..................................................83

15.1. Introduction.........................................................................................................83

15.2. Employee Training..............................................................................................84

15.3.

Personal Protective Equipment...........................................................................84

15.4. Preparation for the Unusual.................................................................................85

15.5.

Construction, Repair and Maintenance in Confined Spaces...............................85

15.6.

Blood-borne and other Pathogen Safety.............................................................86

15.7. Accident Prevention Responsibility....................................................................87

15.8. Signs that Communicate Effectively...................................................................87

15.9.

Conclusion...........................................................................................................88

Subject Index.................................................................................................................89


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CH APTER 1

SIT E ROA DS

1.1. INTRODUCTION

Road access is a vital part of landfill operation and must be appropriately planned and

budgeted for. It is imperative that landfill site roads are adequate for their intended

use in providing safe and unhindered access to and from the tipping face at all times.

Access for landfill equipment also needs to be considered and often this needs to be

on separate roads or equipment tracks.

Prevention of damage to vehicles and quick turn around times are essential in

maintaining good customer relations at a landfill site. In addition, maintaining

continuous access to the tipping face reduces reliance on emergency tipping areas,

and minimises the risk of forced of site closure due to the tipping area becoming

inaccessible.

All landfill roads need to be well graded, and kept mud and debris free to the extent practicable, and with adequate drainage. Maintenance must be given high priority as

early action in addressing road problems will usually minimise the need for major

repairs over the long term. Use of a graded running course on main site roads is

usually essential to ensure all weather access ( sometimes waste materials (either as-

received or re-processed), can be used for this purpose.

1.2. ROAD TYPES

Landfill roads can be divided into four types:

! Approach roads and entrances (with approach roads usually part of a regional

road network)! Primary Access roads ( Internal roads to reception / weighbridge and internal

site road junction

! Secondary Access roads ( Main internal roads to operational area

! Tertiary Access roads ( Temporary roads within the operational area

Where possible, all main access routes should allow for two-way traffic flow.

However, where this is not possible the provision of passing bays must be considered

and is usually essential at other than very small sites. The design standard for each of

these road types will be very different as described below.

1.3. SITE APPROA CH AND ENTR ANC E RO ADS

Main site approach road design should be to local highway standards, including road

markings and speed limit signs, based on anticipated traffic usage. Drainage with


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cesspits is desirable to enable both the entry road and adjacent approach roads to be

kept clean.

Care must be taken not to under-design the pavement construction as repairs related to pavement failure and pothole development in this crucial area can lead to significant

difficulties, particularly if site user vehicles need to queue onto a public highway.

Entrances will typically be bell-mouthed, and sealed with either tarmac or concrete. A

minimum distance into the site of 25m from the entry point is desirable before

reducing road configuration to a lower standard. Entrance roads are usually provided

with kerb and channel, a camber to ditches on either side, or sloped to a ditch running

along one side of the road, to enable mud and water to drain to the side of the road.

In order to present a good image at the site entrance, visibility splays should be

grassed and/or landscaped, with due regard to any sight distance or other height

restrictions applicable, and should be regularly maintained. In addition, site entrancesignage must be neat, functional, well-planned and located. A site approach road is

shown at Figure 1.1.

Figure 1.1. Site approach road

1.4. PRIMARY ACCESS ROADS

This type of access road typically runs from the site entrance to the site reception

facilities and to the egress point of any wheel cleaning measures. It should be paved

with either tarmac or concrete, have lane markings and be designed to allow for

surface water run off, either by cambering to ditches on either side, or by sloping to a

ditch running along one edge. Appropriate drainage and silt traps (or cesspits) should

be provided for litter, debris and sediment control. A primary access road is shown at

Figure 1.2.

The road surface must be capable of being regularly watered down and swept.

Installing speed humps should be avoided (these can be when wet and in winter),

unless required for safety reasons. Speed humps can also make road sweeping

difficult and prove to be collection points for mud and debris. However, where speed


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control is necessary, consideration should be given to chicane-type features to enable

cars, but not waste haulage and other heavy vehicles, to manoeuvre around them.

Figure 1.2. Primary access road

To avoid the need for speed humps, barrier arms can be installed and may be an

appropriate solution. Barriers help to control vehicle speed, prevent access to

unauthorized vehicles and make it much easier to sweep, clean and maintain the site

roads (Figure 1.3).

Figure 1.3. Barriers at a primary access road

1.5. SEC ONDAR Y A CC ESS RO ADS

Hard-core (gravel) roads, as shown at Figure 1.4, can be used to provide secondary

access within the site active area. However, due regard should be given to the length

of road and the length of time it will be utilized. It may be more economical over the

long term, when both construction and maintenance costs are considered, to provide a

sealed / paved road for main secondary roads and perimeter access roads.


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Hard-core roads should always be properly designed and where roads are formed over

waste usually will be underlain with geofabric to facilitate drainage and prevent stone

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recovery of the majority of material for re-use when the tipping area is shifted.Grading to provide drainage is not essential, but if it is possible to have the finished

surface above waste level, less maintenance will be required. Ruts should be regularly


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addressed, mud scraped off and drivers encouraged to split their approach in working

face apron areas to reduce rut formation.

Single-track roads should be avoided by providing a width of at least one-and-a half-tracks.

Compactors and other heavy site mobile plant should avoid crossing or using the

tertiary access roads and separate tracks should be provided for machinery that needs

to be moved away from the active area for maintenance.

The better tertiary access roads are maintained, the greater the corresponding

reduction in the impact on other access routes. In particular, the carry-over of mud can

be reduced and the effectiveness of wheel-cleaning measures can be improved by

keeping tertiary access roads at a good quality level, although weather and the nature

of available site road making materials can often impact on this aspect of operation.

1.7. CONCLUSIONS

It is important to give vehicle access high priority at any landfill site. Good access

roads can contribute significantly to customer satisfaction by reducing vehicle damage

and enabling quick turnaround times, as well as reducing site operations costs.

Road maintenance is of fundamental importance and appropriate design is essential to

meet service requirements. Rutting and potholes will trap water, which can damage

roads and potentially result in the need for major repairs, as well as disrupting face

access. Recovered waste or other surplus site materials are often suitable for use in

forming temporary site roads, but such materials should be carefully selected to avoid

introducing problems with maintenance, or increasing puncture risk to road vehicletyres.


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CH APTER 2

TH E USE OF DA ILY CO VER

2.1. INTRODUCTION

The regular application of daily cover soil (Figure 2.1), or an alternative such as

tarpaulins or an artificial (alternate daily cover) material is perhaps the most

fundamental control on direct effects arising from waste landfilling. Sites with poor

daily cover practices are often subject to bird, odour, vermin, litter and surface water

quality problems.

The most fundamental control to achieve good landfill performance is to regularly and

completely cover the waste and to ensure it remains covered in all areas other than the

active face, which should be kept as small as practicable.

Figure 2.1. Application of daily cover

2.2.

OBJECT I VES OF DA ILY CO VER

The key objectives of placing daily cover are to:

! Minimise windblown-litter

! Control odours

! Prevent birds from scavenging

! Prevent unauthorised scavenging by humans

! Prevent infestation by flies and vermin

! Reduce the risk of fire

! Provide a pleasing appearance

!

Shed surface water and minimise contamination of runoff.


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2.3. DISCUSSION

2.3.1. Windblown Litter

Windblown litter is created when waste is deposited and is not controlled by

compaction and/or cover soil. The use of modern equipment such as a bulldozer or

steel-wheeled compactor ensures that material capable of being windblown is

compacted and worked into the waste surface. The regular application of daily cover

throughout the day, and completely at the end of the day is a key control over litter at

most sites. However, under some conditions (e.g., where a site is windy, where cover

soil is in short supply, or where artificial cover methods such as tarpaulins are being

used) this may not be enough on its own to provide effective litter control and

additional measures to control litter may be needed (see the Guideline for Litter

Control).

However, windblown litter can occur simply as a result of poor compaction of the

waste, or as a result of weather conditions. Both are issues which can be effectively

addressed by the regular application of daily cover soil.

2.3.2. Odour

While the placement of daily soil cover does not provide a completely sealed surface,

it is shown to be an effective control on odour. But daily cover alone will not be an

effective odour control measure at most sites. However, when combined with a

proper cell development sequence, the use of thicker intermediate cover layers and a

positive gas extraction system, daily cover provides a vital and effective odour control

measure.

2.3.3. Scavenging by Bi rds

Scavenging by birds, particularly gulls or the like, occurs as the waste is tipped and

exposed as a food source is readily available. Prompt compaction and covering of

the waste with soil (enhanced by minimising the size of the working face) minimises

the availability of the food source. Regular application of a thick layer of soil will

reduce the attractiveness of a site as a food supply to gulls and is essential to

discourage birds like crows and raptors that tend to dig through the cover to unearth

food waste. It is essential to recognise that while closing down the food supply by

applying daily cover is an effective control measure, it may take some time forimprovements (by way of reduced bird numbers) to be noted at sites where birds are

well established due to conditioning of the bird population. In such cases, other

control methods may also be needed (refer to Guideline on Bird Control).

2.3.4. Scavenging by H umans

Scavenging by humans occurs at some sites, particularly those in poor countries and

where security measures are inadequate in preventing entry to the site at the end of a

working day. The application of daily cover, combined with compaction of the waste

in accordance with good landfill practice will reduce the ability to access and sort

through the waste and make a site less attractive to scavengers. However, daily cover

alone will not eliminate scavenging where the waste has a value locally: othermethods will also be required.


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2.3.5. Infestation by Flies and Vermin

Practical experience, supported by experimental work, has demonstrated that the

regular placement of cover soil will prevent the emergence of flies. The soil coverlayer has to be a minimum of 100mm thick to be effective in this regard. Application

of a thick layer of daily cover (200mm minimum) has also been shown to be very

effective in controlling rats and other vermin such as feral animals as over a period of

time, it simply makes accessing the food source too difficult to be attractive to

animals. Insecticides and rodenticides can be an effective supplement to daily cover

practices, but are expensive to implement on a large scale and will provide only a

short term response if daily cover practices are not kept at a high, consistent level.

2.3.6. Fires

Fires are a concern for the management of any landfills and have been synonymous

with open dumps. Fires typically result from poor operational practice, including at

open dumps where waste is often deliberately set on fire to create more space.

Daily cover reduces the ingress of air to the waste and hence promotes the onset of

anaerobic conditions. It also isolates the waste from the surface and reduces the

potential for accidental or deliberate fires being started.

2.3.7. Visual Appearance

The use of daily cover always improves the visual appearance of a landfill site. While

at some sites visual appearance may only be an issue when the waste surface nears

final levels, a neat site free of windblown litter sets the first key impression of the

level of management applied at a site and is an essential consideration at a modern,

well run landfill site. When viewed from the site boundary a well managed, well-

compacted, fully covered landfill surface can give a uniform appearance and be

aesthetically pleasing to the eye. In this respect, the use of daily cover does enhance

site performance and give the public and local community confidence in the

operational standards being applied at a site, particularly where neighbours are in

relatively close proximity.

2.3.8. Surface Water Control

Daily cover, when loosely placed will have little impact on surface water

management. However, as moisture is an essential component for waste degradationmany believe it should be allowed to penetrate the waste to speed up the stabilisation

process.

As cells are developed, graded areas of daily cover are typically amended with the

application of further soil as intermediate cover layers. These thicker soil areas are

compacted, graded and sloped to surface water drains to ensure that runoff from larger

completed cell areas is not contaminated by waste materials.

2.4. DAIL Y COV ER TYPES

The types of daily cover available can be split into three generic material types as

shown in Table 2.1.


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Table 2.1. Types of daily covers

Inert Waste Der ived Artificial / Synthetic

Free draining soils Paper pulp Synthetic foams

Non draining soils Pulped paper Geotextile matting

Contaminated soils Shredded wood Plastic film

Foundry sand Shredded tyres Synthetic mesh

Colliery waste Shredded plastics Hessian fabric

Quarry wasteRecycling process

wasteTarpaulins

Ash Shredded green waste

River siltsPulverised household

waste

Compost

There are clearly advantages and disadvantages from the use of each of these generic

cover types as summarized in Tables 2.2, 2.3, 2.4 below.

Table 2.2. Advantages and disadvantages of inert wastes used as daily cover

Advantages Disadvantages

Ease of application and

availabilityConsumes void space

Visual appearance Wheel cleaning often necessary

Non combustible Potentially dusty

Can be applied using on-site

plant

Can be relatively impermeable to

leachate and landfill gas

Can be permeable to landfill gas

and leachatePoor traction for certain materials

Good traction quality for some

materials


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Table 2.3. Advantages and disadvantages of wastes derived materials used as dailycover


Utilises a waste stream Can be ineffective in controlling odours

Permeable to landfill gas and leachate Processing required

Good running surface Can attract birds and vermin

Preserves void space for waste Possible fire hazard

May be biodegradableDust can be a problem particularly from

shredded wood

Table 2.4. Advantages and disadvantages of artificial/synthetic materials used as dailycover


Useful on inclined surface May not suppress odour

Readily deployed with modifications

to existing plantMay not prevent fly infestation

Saves void space Potential fire risk

Permeable to landfill gas and leachate

and biodegradableUseful as daily cover only

Good visual appearance Cost

Not suitable for trafficked areas

Colour

Difficult to apply under adverse weather

conditions

Difficult to apply progressively during

the working day


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Figure 2.2. Application of Geotextile Matting

2.5. DAILY COVER APPL ICAT ION

Ease of application is a factor that needs to be taken in to account when selecting the

type of daily cover for use at a particular site. When selecting natural cover soils, it

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clays. However, each soil type has advantages and disadvantages and the reality is

that most sites tend to use whatever is available on site, as effectively as is possible.

The surface upon which the daily cover is applied should be well compacted and free

from major ruts and depressions. A poorly compacted and graded waste surface will

result in more daily cover being used than is desirable, which will result in a loss of

void availability for waste as well as higher disposal cost.

2.6.

SOIL USE PLA N

It is important, when using site soils as daily cover, to ensure that the soils are used

effectively. A cover soil plan can be developed, as follows:

! Ascertain the volumes of cover used on a day-to-day basis

! Stockpile soil cover close to the active face for ready access

! Ensure the machine operative is aware of the quantity available

! Ensure machine operator prepares the surface to minimise soil use and that previous layers are stripped back and stockpiled for re-use before fresh waste

is placed each day

! Record actual volumes used

! Review cover usage regularly

! Amend planned usage to reflect the effectiveness being achieved.

2.7. CONCLUSIONS

It is difficult to be prescriptive about what materials should be used for daily cover

and the issue must be considered on a site by site basis. However, it is clear that

regular and thorough application of daily cover is a fundamental control for effective

management of a modern, well engineered landfill site.

Many of the outcomes achieved by the use of daily cover can be achieved (at least in

part) by other means. However, daily cover provides a simple, robust control on manyof the key effects of landfilling and generally speaking is an essential requirement at

any well managed site.


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CH APTER 3

B IRD CON TRO L

3.1. INTRODUCTION

Birds frequenting a landfill site do so mainly for food. They are seen as noisy and

messy, and commonly they can be carriers of pathogens or they can be the cause of

local nuisance through fouling of roofs and roof-water supplies. Also, in some

instances birds can pose a threat to the safety of aircraft where landfills are located

near commercial airports. If birds are given a dependable food supply and a safe

environment (suitable resting or roosting areas) their rate of breeding will increase, as

it is shown in Figure 3.1 this will the potential to attract more birds from a greater

distance around the landfill site.

Figure 3.1. Birds at the landfill

3.2. B A C K G R O U N D

Before bird numbers can be controlled at a landfill, it is important to have an

understanding of the requirements that birds have and what makes a landfill site

attractive to them. All birds have three key drivers: food supply, rest, and the ability

to breed. Landfill sites can offer a suitable environment for all of these, depending

on the type of bird.

When a bird infestation issue is to be dealt with, it must be taken into account that

birds can become quickly accustomed to the usual methods of bird control that are

used. The method of control must therefore be varied, as required, to provide aneffective overall control strategy. Provided that birds can be identified by species it is

often possible to use their instinctive and learned behaviour against them to minimise


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their level of nuisance. It is possible to keep disturbing accumulations of birds and to

progressively remove their food sources, resting and roosting places, until the birds

find the landfill site no longer attractive. This process is the key to an effective birdcontrol strategy.

3.3. HIER ARCH Y OF CONTRO LS

! Operational Practices

! Gas Guns and Direct Shooting

! Heli-kites and Balloons

! Distress Calls

! Signal Pistols and Cartridges

! Falcons and Raptors

! Wires and Screens

3.4. OPERATI ONA L PRACT I CES

Effective management of the working face is the starting point when attempting to

reduce bird numbers. All waste that could be a source of food should be compacted

and covered with soil on an ongoing basis throughout the day, and completely by the

end of each working day, thus removing access to the food source.

Restored areas and non-operational areas of the site are the next areas that require

attention. It is essential that there are no areas of exposed waste, or areas where

water can pond and allow the birds to stand, drink and clean themselves.

Where there are restored areas the grass should be allowed to grow while the landfillsite is still operational. The grass should be allowed to grow to a height of at least

225mm, as this will deprive most birds of areas to rest as it makes it difficult for them

to land and to take off. Many bird species also fear predators where long grass is

present.

3.5. C O N T R O L M E T H O DS

Once an effective suite of site operational control measures has been put in place, a

number of direct methods of control can be employed. These control measures

should be varied on a regular basis to ensure that the birds are continually unsure of

the type of danger that they are being exposed to, and hence tend to react by re-

locating.

Lethal methods of bird control are sometimes not acceptable and may contravene

local legislation. Also, public concern over lethal methods of control may produce

adverse local comment. However, shooting and poisoning do have a role at some

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and can be so deterred, sometimes in large numbers. Any shooting or poisoning

programme should only be undertaken by licensed persons and under strict control.

Firearms, ammunition and poisons need to be properly and securely stored on site.

Gas guns (bird scarers) are a non-lethal alternative to shooting or poisoning that are

simple to operate and can be very effective for short periods at a time. Theireffectiveness depends upon the gas guns being moved around the site on a regular

basis. However, this method of control can become a nuisance to neighbours,


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particularly if the hours of operation of the equipment fall outside usual business

hours.

Heli-kites and balloons can be very effective for 2 or 3 days at a time and again must be moved around the site regularly. If these are left out on site over night during the

summer periods in an unsecure area, theft and vandalism may be a problem.

Bird scaring tapes and broadcasting equipment are also available and can be effective

when the speakers are mounted onto the compactor. Again the use of this type of

equipment needs to be varied and used somewhat sparingly to obtain a satisfactory

result. It is recommended that when purchasing this type of equipment the bird

distress sounds are purchased in a digital format and used with appropriate equipment

as cassette tapes may jam or become scratched and ineffective. The distress call mix

needs to be site-specific to be effective.

Signal pistols with bird scaring cartridges can also be used. To use this equipment afirearms certificate may be required, a secure location required for storing pistols and

cartridges, as well as specialist training in their use, as is the case with live firearms.

As with the gas gun, this control method has the potential to be a nuisance to

neighbours.

Falcons and other raptors which are shown at Figure 3.2 can be used as an active bird

deterrent. Usually this is achieved by contracting a specialist company to fly birds of

prey around the site. These can be very effective, but the falconer will need to be

fully inducted in the requirements of any Health and Safety policy and should be

treated as an external contractor working on site.

Figure 3.2. Falcons used as bird deterrent

Wires and screens can be used to limit bird flight and discourage birds from settling.

The spacing of wires must be such that birds cannot readily fly between them (Figure

3.3). Screens must be close enough to the working area to prevent birds from landing

and taking off and this method is only likely to be suitable for larger birds. As a last

resort the working area can be completely enclosed, but this can lead to operational problems if the area enclosed is not large enough to allow vehicles to turn or high


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enough to allow them to tip. However, netting off and achieving an enclosed area

does have the added advantage of providing additional litter control.

Figure 3.3. Spacing of wires

3.6. CONCLUSIONS

The methods described offer guidance on bird control measures that can be employed.

To be successful it has been shown that methods of physical bird control or deterrents

must be varied on a regular basis. All approaches that work well depend on human

presence and human interpretation of the situation, backed by positive and appropriate

action. This starts with effective control of the food source by covering the waste

effectively and regularly, and thereafter by implementing a hierarchy of measures thatultimately result in the landfill being an unattractive place for bird roosting and

breeding. Many species of birds which frequent landfill sites have become used to

human presence, so affirmative action is often necessary to get on top of a bird

problem. The key to success lies in not allowing birds to establish their presence at a

landfill in the first place. However, if birds have established then a site-specific,

targeted programme of control methods can usually overcome the problem, although

in some cases this can take a considerable period of time to achieve.


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CH APTER 4

W H E E L C L E A N I NG

4.1. INTRODUCTION

The arrangements needed at a Landfill to prevent mud or other debris carry over onto

public highways are very much site-specific. Where licences or permits are in place,

conditions are usually included that are aimed at minimizing the carry over of mud or

debris onto the public road network and such conditions are usually enforceable.

Carry over of mud onto the highway can also be an offence under local legislation in

some situations.

4.2. OPTIO NS FO R MINIMI ZING NUISANC E

The following opportunities exist for minimising mud and debris carryover and hence

nuisance, and enable a hierarchy of controls to be put in place:

!

Increasing the length of paved internal site roads (queuing length)! Using paved access routes

! Mechanical road sweeping

! Wheel spinners (wet or dry)

! Wheel wash facilities (bath or spray)

! Adequately maintaining on site roads

! Use of daily cover.

4.3. HIER ARCH Y OF CONTRO LS

The following broad hierarchy of controls is suggested:

!

Keep the working area and site access roads as free of mud as possible, and ina good state of repair.

! Use a paved road from the public highway to the site reception facilities and

weighbridge, and from any wheel washing facility to the site exit. A longer

length of road assists. Note that speed bumps will invariably shake mud from

vehicles (even after a wheel wash) and increase the need for road cleaning

operations as well as making road cleaning more difficult.

! Adopt mechanical road sweeping (either self-propelled or tractor drawn) is an

essential routine maintenance activity on paved roads.

! Apply other vehicle cleaning methods selected to suit site conditions and usethem as part of routine operations:

-

Shaker bars

- Wheel spinner ( dry / wet


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-

Wheel wash (bath)

- Wheel wash (spray)

-

Hand held water lance.

4.4. DISCUSSION

The carry over of mud or dirty water onto public roads or footpaths is unsightly, can

create a nuisance, and can result in accidents. It can also result in problems with

regulators, or even prosecution under local laws.

The routine use of an appropriate mix of the techniques described above will be of

great benefit in preventing the carry over of mud or other debris onto public roads.

For each and every method to be effective, regular use and good maintenance of

equipment and support facilities are essential. In some cases, the level of effort that

needs to be applied to this aspect of site operations may be influenced by climate,

mud or dust and may be strongly seasonal.

It is essential that where abatement equipment is available, that it is regularly used.

The onus is always on the operator to ensure that the use, maintenance and

effectiveness of these control measures is adequate and that these measures are a

routine basis part of the landfill operation.

Where wheel-cleaning facilities are provided they must be located as far into the site

as is practical in relation to paved site roads in order to minimize the carry over of

fine mud or wash water, and to avoid the staining of public roads.

Even where it is considered that the measures that are being undertaken within a site

are fully effective, it is both good public relations and usually a permit to licenserequirement, to carry out a regular programme of road sweeping in the immediate

locality. Where there are pedestrian pavements located near the site, it should be

noted that these too can become soiled and may need to be regularly swept, or cleaned

by water/mechanical means.

4.5. CONCLUSIONS

The operator of a well managed landfill will routinely devote resources to ensuring

that there is minimal impact from the operations on the external road network (Figure

4.1).

Figure 4.1. External Road Network


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This will minimise the potential for public complaints, or issues with local regulators.

Careful, structured and routine attention to the hierarchy of control methods available

will typically result in minimal nuisance from mud and debris from a landfill site andwill reflect a professional, well managed landfill operation.


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CH APTER 5

L I T T E R C O N T R O L

5.1. INTRODUCTION

A frequent cause for concern for sanitary landfill management is the control of litter.

Litter is unsightly, can result in water pollution and can be a nuisance to surrounding

property. Hence issues related to wind-blown litter are a common topic at Site

Liaison Committee Meetings, during the planning process for new landfills, and with

regulators.

Depending on site conditions, litter can be difficult to control and manage. However,

in almost all cases there are methods available that can keep the offsite impact of litter

to a minimum. A site-specific strategy should be drawn up to manage the impact of

litter. Importantly, whatever strategy is introduced, it is noted that this will only be as

good as its implementation. To reduce the risk of opposition or complaints from

neighbours, effective litter control, achieved via a hierarchy of measures, routinely

and thoroughly applied, is an essential site management tool.

5.2. HIER ARCH Y OF CONTRO L MEASURES

A hierarchy of litter control measures is available, based firstly on load containment,

load handling and tipping, and moving through to secondary measures such as mobile

litter screens, nets and litter picking at site boundaries. Each is expanded on from the

overall range of controls that comprises:

! Load control

! Waste handling

! Portable litter screens

!

Semi-permanent fencing

! Bunds

! Litter fencing

! Select tipping areas

! Netted areas

! Designated waste transfer areas

! Methods for handling for lightweight waste

! Restricting operating hours

It is unlikely that any single control measure will be sufficient to combat litter escape

at a site, and it is essential to develop and refine an effective set of control measures

for each situation. These may also vary with location on the site, or seasonally.


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5.3. Methods of Cont rol

5.3.1. Load Control

B2&7* +"5 =56&1578 $ .=&5*- )$=*34 1"+56"7 &5 &= 1"::"n for litter accumulation along

principal site access routes due to loss from waste vehicles to be an issue for landfill

managers. This can be addressed by applying load and waste acceptance controls to

site users. Typically these include measures such as requiring all normal loads to be

covered with nets or tarpaulins. Dry or dusty loads should also be tarpaulin covered.

Regular inspections should be made of access routes with active litter cleanup as

required (often a routine process). Regular inspections should also be made of

incoming vehicles to ensure loads are covered, secure and not contributing to litter.

The ultimate sanction is to refuse entry to insecure loads or to operators who do not

comply with load management requirements.

5.3.2. Waste H andling

Most of the litter lost from landfill sites results from wind acting on the waste at the

point of tipping, as well as initial compaction practices. Litter loss at the point of

tipping can be minimised by:

! Carefully assessing the waste type being handled i.e. dense waste is less likelyto blow about than uncompacted low density waste such as plastic.

! Not tipping loose waste into the wind.

! Using previously tipped waste to cover and/or provide shelter for more

vulnerable (mobile) waste streams.! Partially compacting loose waste before pushing out.

! Using heavier waste to hold down loose waste.

! Pushing waste out carefully and compact as quickly as practicable.

! Keeping the working area as tight as practicable.

5.3.3. Portable Litter Screens

! Use portable litter screens routinely. ! Screens should be placed down-wind and as close to the working face as

possible. !

Screens should be of good solid construction and robust enough to withstandhandling and relocation by machines (preferably they should be provided with

lifting eyes). ! Screens should be cleared frequently to prevent them from becoming

overloaded and potentially being blown over. ! Screens need to be moved as frequently as changes in the wind direction

dictate. ! Damaged screens should be repaired on a regular basis.

5.3.4. Litter Fencing

This type of fencing is usually semi-permanent (covering a significant landfill

development area through until post-closure). Typically it comprises a metal or nylon

chicken wire / fish netting type system and should surround the entire operational


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area. If it is not practical to surround the entire area, fencing should at the very least

cover the downwind side of the common prevailing wind direction. A design that has

been found effective is to use pole and netting fences with an internal return at the topend to catch litter that collects at and travels up the fence with the wind. This type of

fencing is also used to protect restored areas. Again, regular maintenance is essential

if such fences are to prove successful.

5.3.5. Bunds

Soil bunds placed downwind of the operational area can also provide good litter

control. Under most circumstances, litter rolls along the ground. In this case it will

tend to roll over the bund and deposit in the calmer space behind it. The resultant

litter has to be regularly removed if the system is to remain effective.

5.3.6.

Perimeter FencingPerimeter fencing is usually provided mainly for site security, but it can form a last

line of defence for litter. However, cranked tops are usually provided which often

consist of strands of barbed wire which can trap litter but also make it difficult to

remove, so this type of design should be avoided whenever possible. For the same

reason, brambles should not be allowed to grow up perimeter fences, or immediately

in front of them.

Hedging should not be used as a control measure as it can often be difficult to clear.

5.3.7. Select Tipping Areas

In valley or quarry landfill sites it may be possible to identify different areas within

the developed footprint of the site that are out of the wind, hence making it possible to

have more than one working area available to cater for differing conditions.

Alternative tipping areas should be identified for all sites where there is a problematic

prevailing wind direction.

5.3.8. Netted A reas

Full netting systems that completely enclose the working face area and all loose waste

are sometimes required at very windy or exposed sites. These systems can be either

portable or permanent. The portable type can be moved to suit changing operations.

However, this can be a costly and time-consuming task and is usually only adopted atopen sites where other options are not effective.

A permanent netted area has disadvantages related to machine operation and load

access. Net systems may also require double handling of waste, which has cost and

possible odour implications. However, fully netted systems can be very effective and

may be one of the most effective control options available at open, windy sites.

5.3.9. Designated Waste Transfer A reas

At some sites, litter control can be improved by using on-site waste transfer processes

such as waste separation and waste containerisation, or baling. Such measures are

usually only employed if conditions are particularly adverse and large volumes of one particularly difficult waste type are being handled (e.g., non-recyclable plastic).


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5.3.10. Methods for Handling Lightweight Waste

Some lightweight wastes such as plastic (other related non-littering wastes such as ash

or sawdust) can also be managed by excavation of a pit into which they can be tippedin a controlled manner and then immediately covered to avoid wind mobilising the

wastes.

5.3.11. Restr icting Operating Hours

At some sites windy conditions occur at particular times of the day, or seasonally. At

such sites, particularly where load control can be managed by containerising waste, or

by holding it at transfer facilities, restricting operating hours can be a particularly

effective measure for litter control. Where opening hours can be restricted to morning

or evening calm periods for example, or where activities can be suspended entirely on

windy days, management of litter potentially can be greatly simplified.

5.4. CONCLUSIONS

A range of management techniques is available for litter control at landfill sites. If

carefully and routinely Applied there should be few sites where a high level of litter

control cannot be achieved. However, there will be occasions where litter problems

develop, both on and off-site and litter pickers should be deployed immediately when

the windy weather abates to collect the litter. They should start from the furthest most

point that litter has reached, and work back to the site boundary and then internally.

It is also good site public relations to have regular litter pickers deployed along the

access roads and buffer zones around the site to collect litter whether it comes from

the site or not. This engenders a sense of good will with neighbours, which can have

significant benefits with regard to community relations.

There are clearly many techniques available to us for collecting litter. Some of the

simpler control measures are relatively inexpensive to implement as they relate

simply to applying good operational techniques. Other measures can be much more

expensive and a hierarchy of measures needs to be developed specific to each site to

provide the most effective overall solution recognising that litter control must be

given priority in order to avoid visual and environmental contamination problems

from landfilling.


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CH APTER 6

V E C T O R C O NT R O L

6.1. INTRODUCTION

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insects, birds and other animals, each of which can carry disease agents and be a

threat to public health. Birds require special techniques of control and are addressed in

a separate guideline. Each type of vector can live and multiply at a landfill and is

potentially of concern to site operators, regulators, public health professionals, and the

general public. Fortunately, vectors are controllable and should rarely, and even then

only intermittently, be present on a well controlled landfill.

6.2. B A C K G R O U N D

Vector control involves avoiding vectors from living and becoming established on the

landfill by not providing sources of food and water, and/or shelter. The only vectors

that should be observed in any significant numbers at a sanitary landfill should bethose that happen onto the landfill - they cannot be allowed to establish on the site and

so should only be observed intermittently.

6.3. H I E R A R C H Y O F C O N T R O L

Vectors are controlled by a hierarchy of control methods, all aimed at eliminating

vectors tot e greatest practical extent. This hierarchy includes:

! Operational Practices

! Monitoring

! Eradication

6.4. O P E R A T I O N A L P R A C T I C E

The most important control measure used to minimise vector problems at landfills is

the application of daily cover. Cover should be present on all solid waste at all times,

except the tipping face while it is being worked. Daily cover of at least 150mm of

compacted soil or similar material or an effective layer of alternate daily cover (ADC)

should be applied on finished portions of the daily cell during operation and at the

conclusion of daily operations, and not less frequently than once per day. Alternative

daily cover materials such as tarpaulins, foams, granular waste, etc, can be effective

as vector control after careful site-specific evaluation.

Intermediate cover of 300mm (minimum) compacted soil should be used on all areasnot at finished levels, but not to be further landfilled for a period of 30 days or more.


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Final cover is typically applied as each area is brought to finished level through the

operational life of the landfill.

There should be no uncontrolled or uncovered (stockpiled) waste, including litter,tyres, brush, appliances, construction/demolition waste or even inert industrial waste

on the landfill property. The only exception is compactable soil-like inert wastes, such

as ash, but even this waste must be graded and compacted to avoid ponding water.

Tyres, for example, are known to allow insect breeding due to ponding of water, but

can also harbour a variety of other vectors such as rats as shown in Figure 6.1.

Figure 6.1. Typical rat often found at landfills

There should be no ponding water on the landfill property except as designed for

runoff storage or sedimentation. Sedimentation ponds can, however, aid vector

reproduction if not designed and controlled properly so as to minimise stagnant water,

nutrient build-up and plant growth.

Finally, the waste must be compacted and graded at reasonable maximum slopes (see

the Working Face Guideline) to minimise voids within the waste that can harbour

rodents in particular. Rodents and foxes can readily dig into cover soil, but have

much more difficulty digging into compacted solid waste.

6.5. M O N I T O R I N G

Landfill staff should monitor the levels of key vectors on a daily basis as part of daily

management. The option also exists to contract pest control experts to monitor and

control vectors as necessary. Such experts know where to look for evidence of

problems and are able to interpret signs of vector activity. A simple monthly sitewalk-over can provide a baseline of vector activity so changes can be noted and

translated into action. Observations of various droppings, sightings, tracks, insect

counts, etc are useful indicators of activity. Written reports from regular walk-over

assessments should be kept on file so changes that occur over time and in response to

control measures can be assessed.

On-site personnel can also be trained and given the time to perform monitoring on a

regular basis. However, operations staff may not have the expertise, even after

training, to monitor vectors efficiently, and may overlook or minimise the importance

of monitoring. Appropriate systems and professional support are therefore often an

essential management requirement.


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6.6. E R A D I C A T I O N

Eradication of vectors (i.e., where a specific issue is evident beyond the scope of

management using routine control measures), is usually best performed by professionals. They have knowledge of the most effective methods available, some

of which may not be available to the operator, and are able to choose and implement

the best methods. In some cases on-site personnel do carry out eradication (e.g.

shooting gulls or other birds) as well as using widely available baits, traps (as shown

in Figure 6.2) and other techniques.

Figure 6.2. Typical trap that may be used at the landfills

6.7. CONCLUSIONS

Vectors addressed in this Guideline are birds, insects, rodents and other feral animals.The key basis for control is prompt compaction of all solid waste and the application

of compacted soil or other suitable cover, no less frequently than daily. There should

be only one working face unless absolutely necessary for waste segregation or

operational purposes, and there should be no debris or piles of stockpiled waste

outside of the working face. Ponding of water should be limited to designed

sedimentation ponds or water storage lagoons.

Monitoring and eradication of vectors and pests is usually best performed by

specialist firms contracted for that purpose. However, this work can also be performed

by on-site personnel, but only if they are given the appropriate training and time

allowance such that they can do so, on a routine basis. Monitoring should be

performed frequently and even then, only if there have been no problems noted overan extended period. As a minimum, monthly monitoring is recommended.


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CH APTER 7

M A N A G I N G T H E W O R K I N G F A C E

7.1. INTRODUCTION

The working face is the focus of activity at an operating sanitary landfill. It is the area

where waste is deposited by trucks, levelled and compacted, and where daily cover is

applied. It involves waste transport vehicle movement in a potentially congested area,

heavy landfill equipment movement to work the waste and cover, and personnel to

operate equipment and to spot and direct trucks. It is the one location at the landfill

where waste is loose, uncontrolled and exposed. It follows that good working face

management is critical to achieving a good overall standard of landfill operation, and

minimised long-term impact. Conversely, poor working face management has the

potential to result in blowing litter and debris, greater potential for accidents,

inefficient use of airspace, aesthetic problems, traffic movement problems, uneven or

increased long term waste settlement and vector problems.

7.2. PLAC EM ENT OF THE F IRST LA YER OF WASTE

7.2.1. General

The first layer of waste placed in a cell is crucial for the landfill operation. This layer

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(Figure 7.1).

Figure 7.1. Placement of the first layer of waste


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This loose first layer is essential in order to avoid damage to the liner and leachate

collection system as a result of equipment tracking, or the waste itself penetrating the

liner components during initial cell filling. Damage to the base liner system can veryeasily occur if initial cell filling is not carefully managed and such damage can soon

negate good design and construction, and compromise the containment performance

of a landfill.

7.2.2. Construction of the F irst Layer

The correct procedure for the construction of the first waste layer is as follows:

! The access road to the working face must be constructed from the top of the

cell to the bottom in a way that ensures that the landfill vehicles will traffic

over soil ramps and not the bottom of the landfill cell.

! At the end of the access road a relatively wide temporary area must be

constructed for the manoeuvring of trucks.! The first trucks must dispose of the waste at the end of the access road or a

temporary movement area formed on the landfill base.

! Bulky or hard wastes capable of puncturing the liner must be removed.

! Depending on the waste type, the first waste should be deposited at a vertical

layer thickness of at least 50 cm (often up to 1m or more if bagged street

collection waste is used), and this layer must not be compacted, so it then

constitutes a protection layer to the liner and leachate drainage system.

The above procedure ceases when the whole area of the landfill cell base is covered

with waste to a depth of at least 50 cm (1m recommended), so that no landfill

equipment can track in close proximity to the liner or the base drainage system of thelandfill.

7.3. W O R K I N G F A C E M A N A G E M E N T PR O C E D U R ES

7.3.1. Summary

The key elements of good working face procedure can be summarised as:

! Use the smallest area practicable

! Orderly truck movement and unloading on an all-weather surface

! Work wastes together

!

Effective waste placement and compaction! Maintain working face slope

! Keep area drained

! Apply and compact soil cover promptly.

7.3.2. Use the Smallest A rea Practicable

The optimum area of the working face depends on the number of trucks that need to

be managed, and on the landfill equipment. Ongoing reviews should be performed in

order to regularly adapt the working face size to the expected traffic numbers and total

waste input.

An unnecessarily large working face is difficult to control, expensive to run, andunsightly. The exposed waste can lead to vector problems and blowing litter and


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debris. Also, with a larger face area, landfill equipment has a bigger area to deal with

and more cover soil is needed per ton of waste, which in turn reduces landfill airspace

utilization and landfill equipment fuel efficiency.Waste disposal should usually be confined to one operating working face at any time

(there are some situations where more than one face is needed ( usually where waste

inputs are high at a large site or due to adverse weather conditions). The working face

should be only as large as necessary to allow adequate truck movement and unloading

space, as well as efficient operation of landfill equipment. In general, the width of the

working face should allow approximately 4m of width per truck unit unloading.

However, may be impractical to have 4m per truck available at all times if many

trucks tend to arrive over a short period, in which case, a balance must be struck

between the time spent queuing for the trucks and the width of the working face. The

vertical height of the working face should normally be from 2 to 5 meters. Lower face

heights tend to be wasteful of cover, except for small sites. Excessive cell andworking heights result in a long working face slope that can be difficult to control,

other than at sites where there is a large input of waste.

7.3.3. O rderly Tr uck Movement and Unloading

Traffic patterns should be established and must be obvious to drivers. This may

require flags or other markers a= ?*77 $= $ .=/"55*64 ,&>&+, 56$99&1 3&6*15&"+=; E"6

larger sites it may be necessary to have separate roads to and from the face for

incoming and outgoing trucks. Drivers should wait for instructions before discharging

their waste. There must be safety distance between each vehicle of 2-3 m and each

truck should stop at least 2-3 m away from the working face.There should be sufficient space to allow trucks to unload at the foot or top of the

working face as appropriate, and drivers should be encouraged to spend as little time

as possible at the working face, as shown at Figures 7.2.

Figure 7.2. Trucks unloading their waste


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Trucks can potentially unload at the top or bottom of the working face. However,

unless dictated by access road arrangements, it is generally better to unload at the

bottom where there is better wind protection and the trucks are less visible. This modeof operation also allows landfill equipment to push waste up the working face, which

provides more visibility and control, as well as greater compactive effort from landfill

equipment. The difficulty with depositing waste at the bottom of the working face is

that surface water and muddy conditions occurring during wet weather may hinder

truck movement and cause mud-tracking problems.

After the waste is deposited, the crew of the truck should ensure that no bins, covers

or other equipment is left at the working face before exiting the area.

7.3.4. Work Wastes Together

It is generally best to mix the incoming waste and spread and compact it upon receipt

at the working face. The aim is to achieve a homogeneous waste mass within the

landfill, resulting in more uniform decomposition, liquid and gas flow, and settlement.

One exception is waste that can be used for cover or roads, which is often segregated

and stockpiled near the face for that use. Another exception is if large amounts of a

particular waste arrive over a short period, in which case waste placement may be

delayed, depending on waste characteristics, until other waste arrives that can be

mixed in with the stored waste. Such storage (stockpiling) should be temporary and in

any case must not be overnight.

7.3.5. Waste Compaction / Placement

Experience has shown that 3 to 5 passes of heavy equipment over waste placed in300mm ( 500mm loose layers provides the best compaction without unnecessary

equipment use and expense. Fewer passes of the compactor result in a lower density

of the compacted waste (Figure 7.3). More passes generally provide little additional

compaction, but result in significant additional fuel use and wear and tear on

equipment. However, a site-specific assessment of compaction performance should

always be made as the requirements can vary widely depending on the equipment

type and size, and the type of waste being handled.

Figure 7.3. Compaction of the wastes at the landfill


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The optimum waste layer thickness being worked is a function of waste

characteristics and equipment size. Waste that is wet and homogeneous with few

large items may be compacted in thicker layers without compromising waste density,often with a bulldozer alone. On the other hand, waste containing large items such as

appliances or wood may require more passes and thinner layers in order to break and

compact it effectively. Similarly, large, heavy equipment such as compactors may be

able to work effectively with thicker layers, whereas, smaller bulldozers or

compactors may require thinner layers to provide good waste densities.

7.3.6. Working Face Slope

Steep working face slopes result in poor compaction of the waste, equipment

manoeuvrability problems, and may present an equipment stability problem.

Conversely, a flat working face, while allowing good compaction of the waste,

requires more cover, results in more exposed waste, and can lead to water drainage problems. A slope of between 3 and 10H to 1V will prove optimal for most landfills.

Working at a shallower slope allows compaction equipment to work perpendicular to

the incline, allowing more rapid waste control during heavy waste input periods.

However, slopes up to a steepness of 3H to 1V may be appropriate in certain

circumstances, particularly with relatively dry waste.

Most of the time, the working slope provides the pattern for the expansion of the next

cells of the landfill. In order to avoid using excessive amounts of soil cover material

for appropriate slope formation, it is advisable to work very carefully at the beginning

of landfill cell development to optimise face management.

7.3.7. K eep the Working Area Well Drained

Water can impede working face activity by slowing truck movement in muddy

conditions and can cause traction problems for landfill equipment. It can promote

mud-tracking problems and will also attract vectors. A general rule is to avoid flat

areas on a landfill and to promote drainage away from the working face and into the

waste mass within the operational area at all times.

7.3.8. Apply and Compact Cover Soil Prompt ly

Cover soil (or appropriate Alternate Daily Cover if used) should be applied to the

working face whenever operations are suspended, such as at the end of the workingday, or over weekends. In addition, cover should be applied more frequently across

the top and to any exposed sides of the daily cells throughout the day if at all possible.

All waste should be completely covered with a layer of cover soil (or appropriate

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